318 to 360

With regards to a 318 I dont think you'll see much difference between the 308 and the regular 360 la head. 308 head still has an open combustion chamber like the regular la. Only real difference is the exhaust port is much better but still not as good as the magnum.

Just go for a regular smog era 360 head. Dont even bother porting it,the teen cant use that much port. You will need to get the compression back up as the chamber cc is around 73-75. Keith Black 167 hyperuetectic pistons will fix that.

Thats kinda why I would go for the magnum. It brings the compression up to about 9.5:1 with the .028 head gasket without changing pistons.Does not need porting to make good power.

302 head will need lots of porting to be the magnums equal. $$$

308 head breaths better than the regular 360 la head,but the teen dont need that much breathing anyways. Will drop your compression unless you swap pistons.$$$ again

360 la head will lower comp as well. Any la 360 head will have a large ccc combustion chamber including the 308 casting.